Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794

Open
Open
Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
Labels
bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
Milestone
urgent

Description

@amp-59
amp-59
opened on Apr 28, 2024

Zig Version

0.13.0-dev.46+3648d7df1

Steps to Reproduce and Observed Behaviour

Compile and run example program with zig run underestimate_upper_bound.zig
underestimate_upper_bound.zig:

vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}

Output:

zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

Expected Behaviour

The panic condition should match the compile error condition.

Metadata

Metadata

Assignees

No one assigned

    Labels

    bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.

    Type

    No type

    Projects

    No projects

      Milestone

      Relationships

      None yet

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      No branches or pull requests

      Issue actions

      , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
       blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

      Skip to content
      Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
      Open
      Open
      Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
      Labels
      bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
      Milestone
      urgent
      Description
      @amp-59
      amp-59
      opened on Apr 28, 2024
      Zig Version
      0.13.0-dev.46+3648d7df1
      Steps to Reproduce and Observed Behaviour
      Compile and run example program with zig run underestimate_upper_bound.zig
      underestimate_upper_bound.zig:
      vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
      Output:
      zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

      Expected Behaviour
      The panic condition should match the compile error condition.
      Metadata
      Metadata
      Assignees
      No one assigned
        Labels
        bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
        Type
        No type
        Projects
        No projects
          Milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

          Skip to content
          Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
          Open
          Open
          Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
          Labels
          bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
          Milestone
          urgent
          Description
          @amp-59
          amp-59
          opened on Apr 28, 2024
          Zig Version
          0.13.0-dev.46+3648d7df1
          Steps to Reproduce and Observed Behaviour
          Compile and run example program with zig run underestimate_upper_bound.zig
          underestimate_upper_bound.zig:
          vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
          Output:
          zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

          Expected Behaviour
          The panic condition should match the compile error condition.
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
            Type
            No type
            Projects
            No projects
              Milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
              Open
              Open
              Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
              Labels
              bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
              Milestone
              urgent
              Description
              @amp-59
              amp-59
              opened on Apr 28, 2024
              Zig Version
              0.13.0-dev.46+3648d7df1
              Steps to Reproduce and Observed Behaviour
              Compile and run example program with zig run underestimate_upper_bound.zig
              underestimate_upper_bound.zig:
              vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
              Output:
              zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

              Expected Behaviour
              The panic condition should match the compile error condition.
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                Type
                No type
                Projects
                No projects
                  Milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions
                  
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

                  Skip to content
                  Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
                  Open
                  Open
                  Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
                  Labels
                  bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                  Milestone
                  urgent
                  Description
                  @amp-59
                  amp-59
                  opened on Apr 28, 2024
                  Zig Version
                  0.13.0-dev.46+3648d7df1
                  Steps to Reproduce and Observed Behaviour
                  Compile and run example program with zig run underestimate_upper_bound.zig
                  underestimate_upper_bound.zig:
                  vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
                  Output:
                  zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

                  Expected Behaviour
                  The panic condition should match the compile error condition.
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                    Type
                    No type
                    Projects
                    No projects
                      Milestone
                      Relationships
                      None yet
                      Development
                      No branches or pull requests
                      Issue actions
                      
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                      Skip to content
                      Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
                      Open
                      Open
                      Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
                      Labels
                      bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                      Milestone
                      urgent
                      Description
                      @amp-59
                      amp-59
                      opened on Apr 28, 2024
                      Zig Version
                      0.13.0-dev.46+3648d7df1
                      Steps to Reproduce and Observed Behaviour
                      Compile and run example program with zig run underestimate_upper_bound.zig
                      underestimate_upper_bound.zig:
                      vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
                      Output:
                      zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

                      Expected Behaviour
                      The panic condition should match the compile error condition.
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                        Type
                        No type
                        Projects
                        No projects
                          Milestone
                          Relationships
                          None yet
                          Development
                          No branches or pull requests
                          Issue actions
                          
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                          Skip to content
                          Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
                          Open
                          Open
                          Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
                          Labels
                          bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                          Milestone
                          urgent
                          Description
                          @amp-59
                          amp-59
                          opened on Apr 28, 2024
                          Zig Version
                          0.13.0-dev.46+3648d7df1
                          Steps to Reproduce and Observed Behaviour
                          Compile and run example program with zig run underestimate_upper_bound.zig
                          underestimate_upper_bound.zig:
                          vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
                          Output:
                          zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

                          Expected Behaviour
                          The panic condition should match the compile error condition.
                          Metadata
                          Metadata
                          Assignees
                          No one assigned
                            Labels
                            bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                            Type
                            No type
                            Projects
                            No projects
                              Milestone
                              Relationships
                              None yet
                              Development
                              No branches or pull requests
                              Issue actions
                              
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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                              Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds #19794
                              Open
                              Open
                              Slice operations slice_sentinel and slice_length (with sentinel) produce runtime safety checks testing incorrect (underestimated) upper bounds#19794
                              Labels
                              bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
                              Milestone
                              urgent
                              Description
                              @amp-59
                              amp-59
                              opened on Apr 28, 2024
                              Zig Version
                              0.13.0-dev.46+3648d7df1
                              Steps to Reproduce and Observed Behaviour
                              Compile and run example program with zig run underestimate_upper_bound.zig
                              underestimate_upper_bound.zig:
                              vardest_end: usize=3;
pubfnmain() void {
constsrc_mem: [3:0]usize= .{ 0, 0, 0 };
constsrc_ptr: [:0]constusize=&src_mem;
_=src_ptr[0..dest_end :0];
_=src_ptr[0..][0..dest_end :0];
}
                              Output:
                              zig run underestimate_upper_bound.zig
thread 96316 panic: index out of bounds: index 4, len 3
./underestimate_upper_bound.zig:5:16: 0x1033e49 in main (underestimate_upper_bound)
_ = src_ptr[0..dest_end :0];
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:501:22: 0x1033669 in posixCallMainAndExit (underestimate_upper_bound)
root.main();
^
~/.local/src/zig-linux-x86_64-0.13.0-dev.46+3648d7df1/lib/std/start.zig:253:5: 0x10331d1 in _start (underestimate_upper_bound)
asm volatile (switch (native_arch) {
^
???:?:?: 0x0 in ??? (???)

                              Expected Behaviour
                              The panic condition should match the compile error condition.
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                                bugObserved behavior contradicts documented or intended behaviorfrontendTokenization, parsing, AstGen, Sema, and Liveness.miscompilationThe compiler reports success but produces semantically incorrect code.
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