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Differential D58326

[Driver][Gnu] Support -nolibc flag
ClosedPublic

Authored by phosek on Feb 16 2019, 5:19 PM.

Details

Reviewers
echristo
mcgrathr
Commits
rG37f30231ba75: [Driver][Gnu] Support -nolibc flag
rC354210: [Driver][Gnu] Support -nolibc flag
rL354210: [Driver][Gnu] Support -nolibc flag
Summary

This can be used to disable libc linking. This flag is supported by
GCC since version 9 as well as some Clang target toolchains.

Diff Detail

Repository
rL LLVM

Event Timeline

phosek created this revision.Feb 16 2019, 5:19 PM
Herald added a project: Restricted Project. · View Herald TranscriptFeb 16 2019, 5:19 PM
Herald added a subscriber: cfe-commits. · View Herald Transcript
This revision was not accepted when it landed; it landed in state Needs Review.Feb 16 2019, 6:42 PM
Closed by commit rL354210: [Driver][Gnu] Support -nolibc flag (authored by phosek). · Explain Why
This revision was automatically updated to reflect the committed changes.
Herald added a project: Restricted Project. · View Herald TranscriptFeb 16 2019, 6:42 PM
Herald added a subscriber: llvm-commits. · View Herald Transcript

Revision Contents

PathSize
cfe/
trunk/
lib/
Driver/
ToolChains/
3 lines
test/
Driver/
2 lines
5 lines

Diff 187152

cfe/trunk/lib/Driver/ToolChains/Gnu.cpp

Show First 20 Lines • Show All 512 Lines • ▼ Show 20 Lines if (!Args.hasArg(options::OPT_nodefaultlibs)) {
AddRunTimeLibs(ToolChain, D, CmdArgs, Args); AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
if (WantPthread && !isAndroid) if (WantPthread && !isAndroid)
CmdArgs.push_back("-lpthread"); CmdArgs.push_back("-lpthread");
if (Args.hasArg(options::OPT_fsplit_stack)) if (Args.hasArg(options::OPT_fsplit_stack))
CmdArgs.push_back("--wrap=pthread_create"); CmdArgs.push_back("--wrap=pthread_create");
if (!Args.hasArg(options::OPT_nolibc))
CmdArgs.push_back("-lc"); CmdArgs.push_back("-lc");
// Add IAMCU specific libs, if needed. // Add IAMCU specific libs, if needed.
if (IsIAMCU) if (IsIAMCU)
CmdArgs.push_back("-lgloss"); CmdArgs.push_back("-lgloss");
if (Args.hasArg(options::OPT_static)) if (Args.hasArg(options::OPT_static))
CmdArgs.push_back("--end-group"); CmdArgs.push_back("--end-group");
else else
▲ Show 20 Lines • Show All 2,125 Lines • Show Last 20 Lines

cfe/trunk/test/Driver/nodefaultlib.c

// RUN: %clang -target i686-pc-linux-gnu -### -nodefaultlibs %s 2>&1 | FileCheck -check-prefix=TEST1 %s // RUN: %clang -target i686-pc-linux-gnu -### -rtlib=libgcc -nodefaultlibs %s 2>&1 | FileCheck -check-prefix=TEST1 %s
// TEST1-NOT: start-group // TEST1-NOT: start-group
// TEST1-NOT: "-lgcc" // TEST1-NOT: "-lgcc"
// TEST1-NOT: "-lc" // TEST1-NOT: "-lc"
// TEST1: crtbegin // TEST1: crtbegin
// TEST1: crtend // TEST1: crtend
// RUN: %clang -target i686-pc-linux-gnu -stdlib=libc++ -nodefaultlibs -lstdc++ -### %s 2>&1 | FileCheck -check-prefix=TEST2 %s // RUN: %clang -target i686-pc-linux-gnu -stdlib=libc++ -nodefaultlibs -lstdc++ -### %s 2>&1 | FileCheck -check-prefix=TEST2 %s
// TEST2-NOT: "-lc++" // TEST2-NOT: "-lc++"
// TEST2: "-lstdc++" // TEST2: "-lstdc++"

cfe/trunk/test/Driver/nolibc.c

// RUN: %clang -target i686-pc-linux-gnu -### -rtlib=libgcc -nolibc %s 2>&1 | FileCheck %s
// CHECK: crtbegin
// CHECK: "-lgcc"
// CHECK-NOT: "-lc"
// CHECK: crtend