fix: work around problems with /Zi argument on windows.#1483
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/Zi is not multiprocess-safe; it depends on spinning up an mspdbsrv.exe and interacting with it in unsafe ways. CMake's default debug flags can include /Zi, which uses a shared PDB file via mspdbsrv.exe. When multiple CMake targets build in parallel on Windows, this causes "PDB API call failed" (C1090) errors. Bazel's MSVC toolchain already passes /Z7 (embed debug info in .obj), but CMake's /Zi overrides it. CMake added a better way to interact with this configuration in 3.25 with [CMP0141](https://cmake.org/cmake/help/latest/policy/CMP0141.html). So, my change does two things: 1. Sets the default `CMAKE_MSVC_DEBUG_INFORMATION_FORMAT` to `Embedded`, which is the equivalent of /Z7. 2. Replaces /Zi (if found) in cmake's default flags for `Debug` and `RelWithDebInfo`. (/Zi should only be present here if a project overrides the DEBUG_INFORMATION_FORMAT or if they're on an older cmake). This makes it extremely likely /Zi will not be used unless it is the explicit intention of the rules_foreign_cc user.
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Moving the unreleased tip of main allows to address Bazel 9 related issues instead of patching locally: - bazel-contrib/rules_foreign_cc#1493 - bazel-contrib/rules_foreign_cc#1492 Other notable commits since: - bazel-contrib/rules_foreign_cc#1483 - bazel-contrib/rules_foreign_cc#1490 - bazel-contrib/rules_foreign_cc#1496 Patches 0002 (DY/LD_LIBRARY_PATH) and 0003 (-j on make command line) are still carried locally as neither has landed upstream yet (but we're working on it).
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Moving the unreleased tip of main allows to address Bazel 9 related issues instead of patching locally: - bazel-contrib/rules_foreign_cc#1493 - bazel-contrib/rules_foreign_cc#1492 Other notable commits since: - bazel-contrib/rules_foreign_cc#1483 - bazel-contrib/rules_foreign_cc#1490 - bazel-contrib/rules_foreign_cc#1496 Patches 0002 (DY/LD_LIBRARY_PATH) and 0003 (-j on make command line) are still carried locally as neither has landed upstream yet (but we're working on it).
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Depends on #48082. ### Motivation Moving the unreleased tip of main allows to address Bazel 9 related issues instead of patching locally: - bazel-contrib/rules_foreign_cc#1493 - bazel-contrib/rules_foreign_cc#1492 (`CcInfo` and other `Cc*` symbols) Other notable commits since: - bazel-contrib/rules_foreign_cc#1483 - bazel-contrib/rules_foreign_cc#1490 - bazel-contrib/rules_foreign_cc#1496 ### Additional Notes Patches 0002 (bazel-contrib/rules_foreign_cc#1452) and 0003 (bazel-contrib/rules_foreign_cc#1491) are still carried locally as neither has landed upstream yet (but we're working on it). Co-authored-by: regis.desgroppes <regis.desgroppes@datadoghq.com>
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/Zi is not multiprocess-safe; it depends on spinning up an mspdbsrv.exe and interacting with it in unsafe ways. When multiple CMake targets build in parallel on Windows, this causes "PDB API call failed" (C1090) errors.
CMake's default debug flags can include /Zi. Bazel's MSVC toolchain already passes /Z7 (embed debug info in .obj), but CMake's /Zi overrides it. CMake added a better way to interact with this configuration in 3.25 with CMP0141.
So, my change does two things:
CMAKE_MSVC_DEBUG_INFORMATION_FORMATtoEmbedded, which is the equivalent of /Z7.DebugandRelWithDebInfo. (/Zi should only be present here if a project overrides the DEBUG_INFORMATION_FORMAT or if they're on an older cmake).