Skip to content

[libc++] Simplify the implementation of iostream.cpp #124103

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Merged
merged 1 commit into from
Jan 29, 2025
Merged

[libc++] Simplify the implementation of iostream.cpp #124103

merged 1 commit into from
Jan 29, 2025

Conversation

philnik777
Copy link
Contributor

@philnik777 philnik777 commented Jan 23, 2025 •
edited
Loading

This refactors the standard stream implementation in multiple ways:

  • The streams are now stream_data structs, which contain all the data required for a stream
  • The windows mangling is generated via a macro instead of having magic strings for the different streams. (i.e. it's now only partially magic)

@philnik777 philnik777 force-pushed the simplify_iostream2 branch 3 times, most recently from 4c72022 to 932f1ab Compare January 26, 2025 09:10
@philnik777 philnik777 marked this pull request as ready for review January 29, 2025 15:03
@philnik777 philnik777 requested a review from a team as a code owner January 29, 2025 15:03
@llvmbot llvmbot added the libc++ libc++ C++ Standard Library. Not GNU libstdc++. Not libc++abi. label Jan 29, 2025
@llvmbot
Copy link
Member

llvmbot commented Jan 29, 2025

@llvm/pr-subscribers-libcxx

Author: Nikolas Klauser (philnik777)

Changes

Patch is 29.00 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/124103.diff

6 Files Affected:

  • (modified) libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist (+8-8)
  • (modified) libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist (+8-8)
  • (modified) libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist (+8-8)
  • (modified) libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist (+8-8)
  • (modified) libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist (+8-8)
  • (modified) libcxx/src/iostream.cpp (+59-99)
diff --git a/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
index 50f87bc05ec91c..da6b7c62447159 100644
--- a/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1221,7 +1221,7 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk131__arrive_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseEh', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk132__destroy_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk134__construct_barrier_algorithm_baseERi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk13cinE', 'size': 88, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk13cinE', 'size': 148, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk13pmr15memory_resourceD0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk13pmr15memory_resourceD1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk13pmr15memory_resourceD2Ev', 'type': 'FUNC'}
@@ -1289,9 +1289,9 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk14__fs10filesystem8__removeERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14__fs10filesystem8__renameERKNS1_4pathES4_PNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14__fs10filesystem8__statusERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14cerrE', 'size': 84, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14clogE', 'size': 84, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14coutE', 'size': 84, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14cerrE', 'size': 136, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14clogE', 'size': 136, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14coutE', 'size': 136, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stodERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPj', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stodERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPj', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stofERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPj', 'type': 'FUNC'}
@@ -1300,7 +1300,7 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk14stoiERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPji', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stolERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPji', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stolERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPji', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14wcinE', 'size': 88, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14wcinE', 'size': 148, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15alignEjjRPvRj', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15ctypeIcE10table_sizeE', 'size': 4, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15ctypeIcE13classic_tableEv', 'type': 'FUNC'}
@@ -1325,9 +1325,9 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk15stollERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPji', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15stoulERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPji', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15stoulERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPji', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk15wcerrE', 'size': 84, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk15wclogE', 'size': 84, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk15wcoutE', 'size': 84, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk15wcerrE', 'size': 136, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk15wclogE', 'size': 136, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk15wcoutE', 'size': 136, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk16__clocEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk16__itoa8__u32toaEjPc', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk16__itoa8__u64toaEyPc', 'type': 'FUNC'}
diff --git a/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
index 975d7ef20676b3..4a5cbba272d7b4 100644
--- a/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1221,7 +1221,7 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk131__arrive_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseEh', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk132__destroy_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk134__construct_barrier_algorithm_baseERl', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk13cinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk13cinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk13pmr15memory_resourceD0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk13pmr15memory_resourceD1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk13pmr15memory_resourceD2Ev', 'type': 'FUNC'}
@@ -1289,9 +1289,9 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk14__fs10filesystem8__removeERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14__fs10filesystem8__renameERKNS1_4pathES4_PNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14__fs10filesystem8__statusERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14cerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14clogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14coutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14cerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14clogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14coutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stodERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stodERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stofERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
@@ -1300,7 +1300,7 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk14stoiERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stolERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk14stolERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk14wcinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk14wcinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15alignEmmRPvRm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15ctypeIcE10table_sizeE', 'size': 8, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15ctypeIcE13classic_tableEv', 'type': 'FUNC'}
@@ -1325,9 +1325,9 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk15stollERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15stoulERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk15stoulERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt6__ndk15wcerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk15wclogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt6__ndk15wcoutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk15wcerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk15wclogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt6__ndk15wcoutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt6__ndk16__clocEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk16__itoa8__u32toaEjPc', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk16__itoa8__u64toaEmPc', 'type': 'FUNC'}
diff --git a/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist
index d52678ebabfb15..d2ca73ee032a91 100644
--- a/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1236,7 +1236,7 @@
 {'is_defined': True, 'name': '_ZNSt3__131__arrive_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseEh', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__132__destroy_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__134__construct_barrier_algorithm_baseERl', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__13cinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__13cinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD2Ev', 'type': 'FUNC'}
@@ -1304,9 +1304,9 @@
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__removeERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__renameERKNS1_4pathES4_PNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__statusERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__14cerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__14clogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__14coutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14cerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14clogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14coutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__14stodERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stodERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stofERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
@@ -1315,7 +1315,7 @@
 {'is_defined': True, 'name': '_ZNSt3__14stoiERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stolERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stolERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__14wcinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14wcinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__15alignEmmRPvRm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__15ctypeIcE10table_sizeE', 'size': 8, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__15ctypeIcE13classic_tableEv', 'type': 'FUNC'}
@@ -1340,9 +1340,9 @@
 {'is_defined': True, 'name': '_ZNSt3__15stollERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__15stoulERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__15stoulERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__15wcerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__15wclogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__15wcoutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__15wcerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__15wclogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__15wcoutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__16__itoa8__u32toaEjPc', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__16__itoa8__u64toaEmPc', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__16__sortIRNS_6__lessIaaEEPaEEvT0_S5_T_', 'type': 'FUNC'}
diff --git a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist
index 66a634585e9193..0e8c28fd261ca1 100644
--- a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1234,7 +1234,7 @@
 {'is_defined': True, 'name': '_ZNSt3__131__arrive_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseEh', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__132__destroy_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__134__construct_barrier_algorithm_baseERl', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__13cinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__13cinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD2Ev', 'type': 'FUNC'}
@@ -1302,9 +1302,9 @@
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__removeERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__renameERKNS1_4pathES4_PNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__statusERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__14cerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__14clogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__14coutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14cerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14clogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14coutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__14stodERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stodERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stofERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
@@ -1313,7 +1313,7 @@
 {'is_defined': True, 'name': '_ZNSt3__14stoiERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stolERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stolERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__14wcinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14wcinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__15alignEmmRPvRm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__15ctypeIcE10table_sizeE', 'size': 8, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__15ctypeIcE13classic_tableEv', 'type': 'FUNC'}
@@ -1340,9 +1340,9 @@
 {'is_defined': True, 'name': '_ZNSt3__15stollERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__15stoulERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__15stoulERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__15wcerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__15wclogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__15wcoutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__15wcerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__15wclogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__15wcoutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__16__clocEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__16__itoa8__u32toaEjPc', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__16__itoa8__u64toaEmPc', 'type': 'FUNC'}
diff --git a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist
index 1c247963684cb4..aeb87c482d4ab4 100644
--- a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist
@@ -1205,7 +1205,7 @@
 {'is_defined': True, 'name': '_ZNSt3__131__arrive_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseEh', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__132__destroy_barrier_algorithm_baseEPNS_24__barrier_algorithm_baseE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__134__construct_barrier_algorithm_baseERl', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__13cinE', 'size': 168, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__13cinE', 'size': 280, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD0Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__13pmr15memory_resourceD2Ev', 'type': 'FUNC'}
@@ -1273,9 +1273,9 @@
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__removeERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__renameERKNS1_4pathES4_PNS_10error_codeE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14__fs10filesystem8__statusERKNS1_4pathEPNS_10error_codeE', 'type': 'FUNC'}
-{'is_defined': True, 'name': '_ZNSt3__14cerrE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__14clogE', 'size': 160, 'type': 'OBJECT'}
-{'is_defined': True, 'name': '_ZNSt3__14coutE', 'size': 160, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14cerrE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14clogE', 'size': 264, 'type': 'OBJECT'}
+{'is_defined': True, 'name': '_ZNSt3__14coutE', 'size': 264, 'type': 'OBJECT'}
 {'is_defined': True, 'name': '_ZNSt3__14stodERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stodERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPm', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stofERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPm', 'type': 'FUNC'}
@@ -1284,7 +1284,7 @@
 {'is_defined': True, 'name': '_ZNSt3__14stoiERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocatorIwEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stolERKNS_12basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEEPmi', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__14stolERKNS_12basic_stringIwNS_11char_traitsIwEENS_9allocator...
[truncated]

ldionne
ldionne approved these changes Jan 29, 2025
View reviewed changes
Copy link
Member

@ldionne ldionne left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

LGTM with a few comments. Let's do this instead of #121116

@philnik777 philnik777 merged commit 608012a into llvm:main Jan 29, 2025
11 of 26 checks passed
@philnik777 philnik777 deleted the simplify_iostream2 branch January 29, 2025 20:25
@asmok-g
Copy link

asmok-g commented Feb 12, 2025

Heads-up: We're seeing AddressSanitizer: initialization-order-fiasco warnings after this patch.

@eaeltsin
Copy link
Contributor

Heads-up - we got the
AddressSanitizer: initialization-order-fiasco in std::__u::basic_ostream<char, std::__u::char_traits<char>>::sentry::sentry(std::__u::basic_ostream<char, std::__u::char_traits<char>>&)
that reduced to this commit.

@eaeltsin
Copy link
Contributor

eaeltsin commented Feb 12, 2025 •
edited
Loading

It looks like this AddressSanitizer finding fires on the code that uses cin/cout/cerr streams in constructors of global objects, which should be legit:

These objects are guaranteed to be initialized during or before the first time an object of type std::ios_base::Init is constructed and are available for use in the constructors and destructors of static objects with ordered initialization (as long as iostream is included before the object is defined).

Still need to double-check.

@vitalybuka
Copy link
Collaborator

Looks like false init order fiasco, which are known https://github.com/google/sanitizers/wiki/AddressSanitizerInitializationOrderFiasco#false-positives

However at this is libc++, it's going to bite all users.
Downstream we can suppress with ignore list, but it would be nice do to something like:

#  define STREAM(StreamT, BufferT, CharT, var) stream_data<StreamT<CharT>, BufferT<CharT>> var __attribute__((no_sanitize("address")))

Details
=================================================================
==2956==ERROR: AddressSanitizer: initialization-order-fiasco on address 0x7f63c11a6940 at pc 0x7f63c0d00300 bp 0x7fff16233810 sp 0x7fff16233808
READ of size 8 at 0x7f63c11a6940 thread T0
    #0 in std::__u::basic_ostream<char, std::__u::char_traits<char>>::sentry::sentry(std::__u::basic_ostream<char, std::__u::char_traits<char>>&) libcxx/include/__ostream/basic_ostream.h:198:7
    #1 in std::__u::basic_ostream<char, std::__u::char_traits<char>>::write(char const*, long) libcxx/include/__ostream/basic_ostream.h:478:12
    #2 in AbslFormatFlush absl/strings/internal/str_format/output.h:75:8
    #3 in InvokeFlush<std::__u::basic_ostream<char, std::__u::char_traits<char> > > absl/strings/internal/str_format/output.h:90:3
    ...
    #2 in call_init
    #2 in _dl_init
    #2  in _dl_start_user

0x7f63c11a6940 is located 0 bytes inside of global variable 'std::__u::cerr' defined in 'libcxx/src/iostream.cpp' (0x7f63c11a6940) of size 264
  registered at:
    #0 in __asan_register_globals llvm-project/compiler-rt/lib/asan/asan_globals.cpp:431:3
    #1 in __asan_register_elf_globals llvm-project/compiler-rt/lib/asan/asan_globals.cpp:414:3
    #2 in asan.module_ctor algorithm.cpp
    #3 in call_init
    #4 in _dl_init
    #5 in _dl_start_user

@philnik777 WDYT?

@vitalybuka
Copy link
Collaborator

vitalybuka commented Feb 12, 2025 •
edited
Loading

Actually eliminating dynamic initializer would be even nicer.

Works for me:

constexpr stream_data() {}
constexpr ~stream_data() {}

@philnik777
Copy link
Contributor Author

@vitalybuka marking them sounds good. Can you make a patch?

@vitalybuka
Copy link
Collaborator

@vitalybuka marking them sounds good. Can you make a patch?

What about constexpr? I guess, I updated comment after you read about attribute.

constexpr stream_data() {}
constexpr ~stream_data() {}

@vitalybuka
Copy link
Collaborator

And I can do a patch

This was referenced Feb 13, 2025
Merged
Open
vitalybuka added a commit that referenced this pull request Feb 16, 2025
@vitalybuka
[libc++] Fix initialization-order-fiasco with iostream.cpp constructo…
c6d95c4 
…rs (#126995)

Asan reports it after #124103.

It's know case of false positive for Asan.

https://github.com/google/sanitizers/wiki/AddressSanitizerInitializationOrderFiasco#false-positives

It's can be avoided with `constexpr` constructors.

In general order global constructors in different
modules is undefined. If global constructor uses
external global, they can be not constructed yet.

However, implementation may contain workaround for
that, or the state of non-constructed global can
be still valid.

Asan will still falsely report such cases, as it
has no machinery to detect correctness of such
cases.

We need to fix/workaround the issue in libc++, as
it will affect many libc++ with Asan users.
sivan-shani pushed a commit to sivan-shani/llvm-project that referenced this pull request Feb 24, 2025
@vitalybuka @sivan-shani
[libc++] Fix initialization-order-fiasco with iostream.cpp constructo…
689eb0f 
…rs (llvm#126995)

Asan reports it after llvm#124103.

It's know case of false positive for Asan.

https://github.com/google/sanitizers/wiki/AddressSanitizerInitializationOrderFiasco#false-positives

It's can be avoided with `constexpr` constructors.

In general order global constructors in different
modules is undefined. If global constructor uses
external global, they can be not constructed yet.

However, implementation may contain workaround for
that, or the state of non-constructed global can
be still valid.

Asan will still falsely report such cases, as it
has no machinery to detect correctness of such
cases.

We need to fix/workaround the issue in libc++, as
it will affect many libc++ with Asan users.
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers

@ldionne ldionne ldionne approved these changes

Assignees
No one assigned
Labels
libc++ libc++ C++ Standard Library. Not GNU libstdc++. Not libc++abi.
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.
6 participants
@philnik777 @llvmbot @asmok-g @eaeltsin @vitalybuka @ldionne